As is known, in-the-ear hearing aids are inserted into the auditory canal with the aid of an otoplastic. The microphones in the directional microphone of the hearing aid are arranged such that their highest sensitivity in an inserted state of the hearing aid essentially points horizontally forward.
Furthermore headsets are available on the market, which are used in conjunction with mobile telephones for example. With these devices the telephone signal is transmitted wirelessly or by wire from the telephone to the headset. This is either fixed into the ear using an otoplastic or an ear plug and partially covers the pinna.